A sensor chip for detecting particles may be a biosensor, which may be used for detecting an analyte and may combine a biological component with a physicochemical or physical detector component.
For instance, a biosensor may be based on the phenomenon that capture particles immobilized on a surface of a biosensor, may selectively attach with target particles in a fluidic sample, for instance when an antibody-binding fragment of an antibody or the sequence of a DNA single strand as a capture particle fits to a corresponding sequence or structure of a target particle. When such attachment or sensor events occur at the sensor surface, this may change the electrical properties of the surface which can be detected as the sensor event.
WO 2003/074683 discloses a biochip for capacitive stimulation and/or detection of biological tissue, having a carrier structure, at least one stimulation and/or sensor device that is arranged in or on the carrier structure, at least one dielectric layer, one of the surfaces of said layer being arranged in the stimulation and/or sensor device while the opposite surface of said layer forms a stimulation and/or sensor surface for capacitive stimulation and/or detection of biological tissue, wherein the continuous dielectric layer contains TiO2.
Conventional biosensor chips usually have a sensing surface on top of a processed semiconductor structure. This may also involve the exposure of various metal layers on a surface of such a biosensor chip such as detection electrodes, bonding pads, etc.